Resistance to the quinolones almost always arises from the accumulation of mutations in chromosomal genes responsible for the drug targets, permeability, or active efflux. This resistance can be depicted as a stepwise process in which each step, represented by separate mutations, diminishes susceptibility on average 4- to 8-fold. The precise path followed in this stepwise process differs with t...

This study evaluated bacterial etiology and antibiotic susceptibility in patients diagnosed with community-acquired perforated appendicitis over a 12-year-period. We retrospectively reviewed records of adult patients diagnosed with perforated appendicitis at an 800-bed teaching hospital between January 2000 and December 2011. In total, 415 culture-positive perforated appendicitis cases were ana...

Quinolones are widely used in the treatment of respiratory infections, in large part because of their activity against Streptococcus pneumoniae and other commonly encountered respiratory tract pathogens. Pneumococcal isolates that are resistant to these "respiratory quinolones" have now begun to emerge. Resistance is attributable to mutations affecting the intracellular targets of these drugs, ...

An epidemiological study of filariasis in three villages along the coast at Matara has shown a prevalence of microfilaraemia of 4.4% and a geometric mean microfilaraemia density of 20.6 microfilariae/60ul of fingerprick blood. These are higher than previous values for the area. Prevalence is lower in females compared to males, and also in males under 20 years compared to the older males. Clinic...

With the recent introduction of agents such as gatifloxacin and moxifloxacin, the traditional gram-negative coverage of fluoroquinolones has been expanded to include specific gram-positive organisms. Clinical applications beyond genitourinary tract infections include upper and lower respiratory infections, gastrointestinal infections, gynecologic infections, sexually transmitted diseases, and s...

Ofloxacin and ciprofloxacin resistance (MIC, greater than 4 micrograms/ml) was encountered in 45 of 50 clinical isolates of methicillin-resistant Staphylococcus aureus. None of 20 methicillin-susceptible strains was resistant to the quinolones (P less than 10(-6). Quinolone-susceptible and -resistant isolates did not differ with respect to culture source or bacteriophage type. The future useful...

A new magnesium complex of quinolone antibacterial agent was prepared. This new complex as well as a previously isolated complex of magnesium with ciprofloxacin were tested against various Gram positive and Gram negative microorganisms. Antimicrobial activities were evaluated using the agar diffusion test. The results have shown that all magnesium complexes are significantly less active than th...

Quinolones are a large and widely consumed class of synthetic drugs. Expanded-spectrum quinolones, like ciprofloxacin are highly effective against Gram-negative bacteria, especially Escherichia coli. In E. coli the major target for quinolones is DNA gyrase. This enzyme is composed of two subunits, GyrA and GyrB encoding by gyrA and gyrB, respectively. Mutations in either of these genes cause qu...